Deflection programs are an emerging approach to redirect people who have experienced police contact away from the criminal legal system and toward supportive services, with the goal of improving outcomes for individuals, communities, the justice system, and public health. The Illinois Multi-Site Deflection Initiative is a groundbreaking project aimed at increasing the number of deflection programs in the state to help individuals who come into contact with police. Since 2021, the initiative has been spearheaded by the Illinois Department of Human Services (IDHS) in partnership with the Illinois State Police and Treatment Alternatives for Safe Communities (TASC). As of July 2024, the initiative has 11 programs operating or in the planning stage across 45 counties. IDHS funded the Illinois Criminal Justice Information Authority (ICJIA) to conduct an independent evaluation to study the programs’ planning, development, and operations, as well as assess and measure outcomes. We share the evaluation design, data, and challenges faced during this multi-year evaluation. The evaluation team’s process evaluation assesses program activities and offers recommendations for programmatic enhancement. We offer a point-in-time description of current evaluation activities and future plans.